Objective To investigate the mechanism of expression of TNFα of renal tubular epithelial cells with hypoxia reoxygenation (H/R) and to evaluate the effects of extracts of Picorhiza scrophlariiflora Pennell on it. Methods The cutueled renal epithelial cells were divided into groups: normal control grounp,H/R group, 10μg/ml extracts of Picorhiza scrophlariiflora Pennell H/R group, 100μg/ml extracts of Picorhiza scrophlariiflora Pennell H/R group, 1000μg/ml extracts of Picorhiza scrophlariiflora Pennell H/R group. The flow cytometry was used to detect the oxidative stress as well as expressions of TNFα protein.Real time quantitative reverse transcription-polymerase chain reaction(RT-PCR) was used to detect expression of mRNA for TNFα. Result The oxidative stress in renal tubular epithelial cells was induced after H/R. TNFα protein were increasd after H/R. TNFα mRNA were increasd after H/R.Oxidative stress in renal tubular epithelial cells was inhibited by extracts of Picorhiza scrophlariiflora Pennell with a dose-dependent manner. TNFα protein were inhibited by extracts of Picorhiza scrophlariiflora Pennell with a dose-dependent manner. TNFαmRNA were inhibited by extracts of Picorhiza scrophlariiflora Pennell with a dose-dependent manner. Conclusions Extracts of Picorhiza scrophlariiflora Pennell protected renal epithelial cells against TNFαby inhibiting oxidation after H/R injury.